Since 2019, the Seoul Metropolitan Government has actively pursued the deployment of Cooperative-Intelligent Transport Systems (C-ITS) as a foundation for urban autonomous and cooperative driving. This pilot project established V2X-based communication infrastructure along major arterial roads and bus-exclusive lanes, installing onboard units (OBUs) on approximately 1,600 city buses to deliver real-time traffic safety services. This study conducted a comprehensive evaluation of the C-ITS pilot’s effectiveness by integrating official accident statistics, real-time vehicle trajectory data (PVD), and structured driver surveys to assess outcomes both quantitatively and qualitatively.
The analysis confirmed significant positive effects in traffic safety, driving stability, and user acceptance. Specifically, annual accident frequencies and the severity index (EPDO) showed a raw decline of 9.1% and 21.9%, respectively, with adjusted net effects of 4.3% and 12.0% when controlling for comparison groups. In particular, C-ITS effectively reduced frequent collisions involving buses and pedestrians and improved safety in high-risk acceleration zones. The estimated economic benefit from accident reductions averaged KRW 3.05 billion annually between 2021 and 2023.
In terms of driving behavior, key indicators such as JERK and acceleration noise consistently declined, indicating improved driving smoothness; JERK decreased by 12% and acceleration noise by 8% compared to 2021 levels. Risky driving behaviors, including speeding and abrupt maneuvers, fell by nearly 76% over three years. User satisfaction also improved markedly—drivers reported enhanced awareness and confidence in services like signal alerts, illegal parking warnings, and hazard zone notifications, with average satisfaction scores rising over 5% by 2025.
These findings demonstrate that the Seoul C-ITS pilot achieved multi-dimensional outcomes, including reductions in accident risk, enhancements in traffic flow stability, and increased user trust. The results support the case for continued expansion and institutionalization of C-ITS as a core component of smart urban mobility infrastructure.